Drainage systems for receiving fluid flow are well known in the art. Such systems provide a path for fluid flow from surface areas and often transport the fluid from surface areas directly to the ocean, rivers, lakes, estuaries, streams and the like without regard to the removal of debris, pollutants or other contaminants. For example, because of the Federal Environmental Protection Agency's Clean Water Act, controlling pollution from storm water runoff is receiving ever-increasing attention at all levels of government, Federal, State and local. Federal and state agencies have issued mandates and developed guidelines regarding the prevention of non-point source (storm water caused) pollution that require local governments to act upon or initiate.
Because of the aforementioned mandates, many cities and special districts have developed plans and taken action to prevent storm water pollution. These actions range from those that are educational in nature (labeling storm water inlets with phrases such as “No dumping—Flows into Rivers and Streams”) to active measures to remove pollutants. Such measures generally require the installation of equipment for removing contaminants somewhere between where the storm water enters the drainage system and the ultimate body of water receiving the runoff.
Several types of equipment are employed to reduce pollution and contaminants from storm water runoff. Catch basin filtration systems use devices installed at the point that the storm water enters the drainage system. The water flow is directed through an installed adsorbent material that aids in removing contaminants from the storm water while allowing the water to flow into the drainage system. Such a permanently installed catch basin filtration system is disclosed in U.S. Pat. No. 5,720,574. In addition to catch basin filtration systems, oil/water separators are employed. Such systems generally comprise large underground holding tanks that allow silt and pollutants to settle to the bottom of the tank and the water to flow into the drainage system. Other systems also exist to remove contaminants from water runoff. However, these systems are also generally permanent installations that are expensive to install and maintain. Accordingly, filtration systems for drainage systems that are cost effective and easily maintained are desired.